Power train apparatus

ABSTRACT

A power train may include an engine having a crankshaft and an engine block, a motor housing connected to the engine block and of which a housing hole is formed, a rotor portion connected to the crankshaft through the housing hole and of which a magnet is connected to a first side thereof, a stator portion disposed between the rotor portion and the motor housing, connected to the motor housing and including a coil corresponding to the rotor portion, a transmission connected to the engine block and a clutch selectively transmitting rotation of the rotor portion to the transmission.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No.10-2016-0138358 filed on Oct. 24, 2016, the entire contents of which isincorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a power train apparatus. Moreparticularly, the present invention relates to a power train apparatusprovided with a 2-cylinder engine and a motor.

Description of Related Art

Recently, research has been undertaken to enhance fuel efficiency of avehicle, various researches, such as by designing of a two cylinderengine or a three cylinder engine have been undertaken.

However, enhancing of output and fuel efficiency of the two cylinderengine or the three cylinder engine may be limited according to variousvehicle driving conditions.

Also, the two cylinder engine or the three cylinder engine outputsrelatively serious vibration and applying an element, such as a balanceshaft, for suppressing vibration to the two cylinder engine or the threecylinder engine may be limited.

The information disclosed in this Background of the Invention section isonly for enhancement of understanding of the general background of theinvention and should not be taken as an acknowledgement or any form ofsuggestion that this information forms the prior art already known to aperson skilled in the art.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing apower train provided with a 2-cylinder engine and a motor havingadvantages of reducing vibration and noise and enhancing fuelefficiency.

A power train according to an exemplary embodiment of the presentinvention may include an engine including a crankshaft and an engineblock, a motor housing connected to the engine block and of which ahousing hole is formed, a rotor portion connected to the crankshaftthrough the housing hole and of which a magnet is connected to a firstside thereof, a stator portion disposed between the rotor portion andthe motor housing, connected to the motor housing and including a coilcorresponding to the rotor portion, a transmission connected to theengine block and a clutch selectively transmitting rotation of the rotorportion to the transmission.

The stator portion may include a core plate of which the coil wrapsalong radial direction thereof and a stator plate on which a coil groovewhere the coil is inserted therein is formed.

The coil groove may include a wrapping portion in which the coil isinserted and an inlet portion of which width is narrower than that ofthe wrapping portion for the coil not to be separated.

The engine may be a two-cylinder engine.

The clutch may be a friction clutch which selectively contacts with asecond side of the rotor portion for transmitting rotation of the rotorportion to the transmission.

A receiving portion for seating the stator portion may be formed at themotor housing.

The rotor portion may include a protrude portion connected to thecrankshaft through the housing hole and a disk connected to the protrudeportion and to which the magnet is connected.

A radiate portion may be formed at the rotor portion.

The radiate portion may be formed at an external circumference of therotor portion.

The radiate portion may be formed as a concave shape to an externalcircumference of the rotor portion.

A balance portion may be formed at the rotor portion for compensatingfor imbalance rotational energy transmitted from the crankshaft.

The rotor portion may include a protrude portion connected to thecrankshaft through the housing hole and a disk connected to the protrudeportion and to which the magnet is connected, wherein the balanceportion may be formed at a first side of the disk as a concave shape.

The balance portion may be formed as a fan shape along a circumferentialdirection of the disk.

The balance portion may include a material of which density is lowerthan that of the disk.

The engine may be a two-cylinder engine and the balance portion may beformed at a position corresponding to a connecting rod journal of thecrankshaft.

A power train according to an exemplary embodiment of the presentinvention may include an engine including a crankshaft and an engineblock, a rotor portion including a disk of which a magnet is connectedto a first side thereof vertical to the crankshaft and the rotor portionconnected to the crankshaft; a stator portion disposed between the rotorportion and the motor housing and including a coil corresponding to themagnet and disposed vertical to the crankshaft; a transmission and aclutch selectively transmitting rotation of the rotor portion to thetransmission.

The methods and apparatuses of the present invention have other featuresand advantages which will be apparent from or are set forth in moredetail in the accompanying drawings, which are incorporated herein, andthe following Detailed Description, which together serve to explaincertain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a power train according to an exemplaryembodiment of the present invention.

FIG. 2 is an exploded view of a power train according to an exemplaryembodiment of the present invention.

FIG. 3 is a cross-sectional view of an engine of a power train accordingto an exemplary embodiment of the present invention.

FIG. 4 and FIG. 5 are exploded perspective views of a rotor portion anda stator portion of a power train according to an exemplary embodimentof the present invention.

FIG. 6 is a schematic diagram of a power train according to an exemplaryembodiment of the present invention.

FIG. 7 is a perspective view of a rotor portion of a power trainaccording to an exemplary embodiment of the present invention.

FIG. 8 is a cross-sectional view of a rotor portion of a power trainaccording to an exemplary embodiment of the present invention.

FIG. 9 is a front view of a rotor portion of a power train according toan exemplary embodiment of the present invention.

FIG. 10 is a graph showing power applied to a crankshaft induced byrotation of a power train according to an exemplary embodiment of thepresent invention.

It should be understood that the appended drawings are not necessarilyto scale, presenting a somewhat simplified representation of variousfeatures illustrative of the basic principles of the invention. Thespecific design features of the present invention as disclosed herein,including, for example, specific dimensions, orientations, locations,and shapes will be determined in part by the particular intendedapplication and use environment.

In the figures, reference numbers refer to the same or equivalent partsof the present invention throughout the several figures of the drawing.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of thepresent invention(s), examples of which are illustrated in theaccompanying drawings and described below. While the invention(s) willbe described in conjunction with exemplary embodiments, it will beunderstood that the present description is not intended to limit theinvention(s) to those exemplary embodiments. On the contrary, theinvention(s) is/are intended to cover not only the exemplaryembodiments, but also various alternatives, modifications, equivalentsand other embodiments, which may be included within the spirit and scopeof the invention as defined by the appended claims.

In the following detailed description, only certain exemplaryembodiments of the present invention have been shown and described,simply by way of illustration.

As those skilled in the art would realize, the described embodiments maybe modified in various different ways, all without departing from thespirit or scope of the present invention

A part irrelevant to the description will be omitted to clearly describethe present invention, and the same or similar elements will bedesignated by the same reference numerals throughout the specification.

Throughout the specification and the claims, unless explicitly describedto the contrary, the word “comprise” and variations such as “comprises”or “comprising”, will be understood to imply the inclusion of statedelements but not the exclusion of any other elements.

An exemplary embodiment of the present invention will hereinafter bedescribed in detail with reference to the accompanying drawings.

FIG. 1 is a front view of a power train according to an exemplaryembodiment of the present invention and FIG. 2 is an exploded view of apower train according to an exemplary embodiment of the presentinvention.

FIG. 3 is a cross-sectional view of an engine of a power train accordingto an exemplary embodiment of the present invention and FIG. 4 and FIG.5 are exploded perspective views of a rotor portion and a stator portionof a power train according to an exemplary embodiment of the presentinvention.

Referring to FIG. 1 to FIG. 5, a power train 1 according to an exemplaryembodiment of the present invention may include an engine 10 including acrankshaft 12 and an engine block 14, a motor housing 30 connected tothe engine block 14 and of which a housing hole 32 is formed, a rotorportion 40 connected to the crankshaft 12 through the housing hole 32and of which a magnet 42 is connected to a first side thereof, a statorportion 50 disposed between the rotor portion 40 and the motor housing30, connected to the motor housing 30 and including a coil 42corresponding to the rotor portion 40, a transmission 60 connected tothe engine block 14 and a clutch 70 selectively transmitting rotation ofthe rotor portion 40 to the transmission 60.

In an exemplary embodiment of the present invention, the power train 1includes a motor/rotor portion 20 disposed between the engine 10 and thetransmission 60 and functioning as a flywheel and a motor and thus themotor/rotor portion 20 may reduce vibration of the engine 10 and assistsoutputs of the engine 10.

In the instant case, the motor/rotor portion 20 includes the rotorportion 40 and the stator portion 50.

The rotor portion 40 is directly connected with the crankshaft 12 andstores rotational energy of the crankshaft 12 functioning as a flywheelsuch that the rotator portion 40 may reduce vibration of the engine 10.

The stator portion 50 and the rotor portion 40 functions as a motor forassisting output of the engine 10 and may be a main driving power sourcewhen the engine 10 is not operated. Also, the stator portion 50 and therotor portion 40 outputs compensation torque corresponding to vibrationof the engine 10 so that the stator portion 50 and the rotor portion 40may function as a balance weight.

The stator portion 50 includes a core plate 54 of which the coil 52wraps along radial direction thereof and a stator plate 56 on which acoil groove 57 where the coil 52 is inserted therein is formed. And thestator plate 56 is connected to the motor housing 30.

The motor housing 30 and the stator plate 56 may be assembled by a boltsuch that assembly and disassembly may be easily performed.

Since the stator portion 50 is disposed between the rotor portion 40 andthe motor housing 30, thus assembly may be easily performed and thus themotor/rotor portion 20 may be stable.

A receiving portion 34 for seating the stator portion 50 may be formedat the motor housing 30 and thus increase in length of the motor/rotorportion 20 may be suppressed.

The rotor portion 40 includes a protrude portion 45 connected to thecrankshaft 12 through the housing hole 32 and a disk 44 connected to theprotrude portion 45 and to which the magnet 42 is connected.

The magnet 42 and the coil 52 corresponded to the magnet 42 are disposedvertical to the crankshaft 12.

That is, the magnet 42 and the coil 52 is disposed along radialdirection and thus increase in length of the motor/rotor portion 20 maybe suppressed.

The coil groove 57 includes a wrapping portion 58 in which the coil 52is inserted and an inlet portion 59 of which width is narrower than thatof the wrapping portion 58 for the coil 52 not to be separated.

Since the coil 52 is inserted into the coil groove 57 thus the coil 52may be stably fixed at a predetermined position without additionalparts.

Two connecting rod journals 13 are formed at the crankshaft 12. That is,the engine 10 may be a two-cylinder engine.

Two-cylinder engine may be reduced in size and fuel consumption may beenhanced. However, output of a two-cylinder engine is narrow andrelatively excessive vibration may occur.

However, in the exemplary embodiment of the present invention, the powertrain 1 is provided with the motor/rotor portion 20 disposed between theengine 10 and the transmission 60 functioning as a flywheel and a motorfor reducing vibration of the engine and assisting output of the engine.

The clutch 70 may be a friction clutch which selectively contacts with asecond side of the rotor portion 40 for transmitting rotation of therotor portion 40 to the transmission 60.

FIG. 6 is a schematic diagram of a power train according to an exemplaryembodiment of the present invention.

Referring to FIG. 6, in the exemplary embodiment of the presentinvention, the engine 10 is directly connected with the motor/rotorportion 20 and the clutch 70 is disposed between the transmission 60 andthe rotor portion 40 for selectively connecting the transmission 60 withthe rotor portion 40.

According to the connection state of the clutch 70, the motor/rotorportion 20 may function as a starter motor by supplied electric powerfrom a battery 72, and also may function as a driving power sourceassisting the engine 10.

Also, the motor/rotor portion 20 may function as a generator whenassisting power is not required and the generated electric power isstored in the battery 72.

FIG. 7 is a perspective view of a rotor portion of a power trainaccording to an exemplary embodiment of the present invention and FIG. 8is a cross-sectional view of a rotor portion of a power train accordingto an exemplary embodiment of the present invention.

For easy comprehension, the same or similar elements of the power traindescribed in FIG. 1 to FIG. 6 will be designated by the same referencenumerals and repeated description will be omitted.

A radiate portion 46 is formed at the rotor portion 40.

The radiate portion 46 is formed at an external circumference of therotor portion 40.

The radiate portion 46 is formed as a concave shape to the externalcircumference of the rotor portion 40.

That is, as shown in FIG. 7, since the radiate portion 46 is formed asthe concave shape to the external circumference of the rotor portion 40and thus manufacturing process of the rotor portion is simplified. Andthe rotor portion 40 may circulate air surround the rotor portion 40 tocool the rotor portion 40. Also, area of the surface of the rotorportion 40 is increased due to the radiate portion 46 and thus heattransfer of the rotor portion 40 is increased.

A balance portion 90 is formed at the rotor portion 40 for compensatingfor imbalance rotational energy transmitted from the crankshaft 12.

The rotor portion 40 is shaped as a disk shape and the balance portion90 is formed at a first side of the rotor portion 40 as a concave shape.

That is, the balance portion 90 may be a space function as a balanceweight having negative value. Thus, total weight of the rotor portion 40may be reduced such that the rotor portion 40 may be highly efficient inhigh speed.

The balance portion 90 is formed as a fan shape along a circumferentialdirection of the rotor portion 40.

Thus, cross section along a diameter direction of the rotor portion 40may be simplified and be highly efficient in productivity.

In a modified exemplary embodiment, the balance portion 40 may include amaterial of which density is lower than that of the disk 44 of the rotorportion 40. Thus rigidity of the rotor portion 40 may be maintained.

The balance portion 90 is formed at a position corresponding to aconnecting rod journal 16 of the crankshaft 12.

A connecting rod 82 is connected with the connecting rod journal 16 andthe connecting rod 82 is connected with a piston 80. And the balanceportion 90 is formed at the position corresponding to the connecting rodjournal 16 of the crankshaft 12 for compensating for the imbalancerotational energy transmitted from the crankshaft 12.

As shown in drawings, the engine 10 may be two-cylinder engine includingtwo positions 80 reciprocating with the same phase angles each other.

A shape of the balance portion 90, that is “α” shown in FIG. 9 may bedetermined according to imbalance force due to reciprocal motion of thepiston 80.

FIG. 10 is a graph showing power applied to a crankshaft induced byrotation of a power train according to an exemplary embodiment of thepresent invention.

As shown in FIG. 10, power applied to the crankshaft 12 of the rotorportion 40 with the balance portion 90 may be reduced approximately 50%comparing to the rotor portion 40 without the balance portion 90.

For convenience in explanation and accurate definition in the appendedclaims, the terms “upper”, “lower”, “inner”, “outer”, “up”, “down”,“upper”, “lower”, “upwards”, “downwards”, “front”, “rear”, “back”,“inside”, “outside”, “inwardly”, “outwardly”, “interior”, “exterior”,“inner”, “outer”, “forwards”, and “backwards” are used to describefeatures of the exemplary embodiments with reference to the positions ofsuch features as displayed in the figures.

The foregoing descriptions of specific exemplary embodiments of thepresent invention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteachings. The exemplary embodiments were chosen and described in orderto explain certain principles of the invention and their practicalapplication, to thereby enable others skilled in the art to make andutilize various exemplary embodiments of the present invention, as wellas various alternatives and modifications thereof. It is intended thatthe scope of the invention be defined by the Claims appended hereto andtheir equivalents.

What is claimed is:
 1. A power train apparatus comprising: an engineincluding a crankshaft and an engine block; a motor housing connected tothe engine block and of which a housing opening is formed; a rotorportion connected to the crankshaft through the housing opening and ofwhich a magnet is connected to a first side thereof; a stator portiondisposed between the rotor portion and the motor housing, connected tothe motor housing and including a coil corresponding to the rotorportion; a transmission connected to the engine block; and a clutchselectively transmitting rotation of the rotor portion to thetransmission, wherein a balance portion is formed at the rotor portionfor compensating for imbalance rotational energy transmitted from thecrankshaft.
 2. The power train apparatus of claim 1, wherein the statorportion comprises: a core plate of which the coil wraps along a radialdirection thereof; and a stator plate on which a coil groove where thecoil is inserted therein is formed.
 3. The power train apparatus ofclaim 2, wherein the coil groove comprises: a wrapping portion in whichthe coil is inserted; and an inlet portion of which width is narrowerthan width of the wrapping portion.
 4. The power train apparatus ofclaim 1, wherein the engine is a two-cylinder engine.
 5. The power trainapparatus of claim 1, wherein the clutch is a friction clutch whichselectively contacts with a second side of the rotor portion fortransmitting rotation of the rotor portion to the transmission.
 6. Thepower train apparatus of claim 1, wherein a receiving portion forseating the stator portion is formed at the motor housing.
 7. The powertrain apparatus of claim 1, wherein the rotor portion includes: aprotrude portion connected to the crankshaft through the housingopening; and a disk connected to the protrude portion and to which themagnet is connected.
 8. The power train apparatus of claim 1, wherein aradiate portion is formed at the rotor portion.
 9. The power trainapparatus of claim 8, wherein the radiate portion is formed at anexternal circumference of the rotor portion.
 10. The power trainapparatus of claim 8, wherein the radiate portion is formed as a concaveshape to an external circumference of the rotor portion.
 11. The powertrain apparatus of claim 1, wherein the rotor portion includes: aprotrude portion connected to the crankshaft through the housingopening; and a disk connected to the protrude portion and to which themagnet is connected, wherein the balance portion is formed at a side ofthe disk as a concave shape.
 12. The power train apparatus of claim 11,wherein the balance portion is formed as a fan shape along acircumferential direction of the disk.
 13. The power train apparatus ofclaim 11, wherein the balance portion includes a material of whichdensity is lower than density of the disk.
 14. The power train apparatusof claim 1, wherein the engine is a two-cylinder engine; and the balanceportion is formed at a position corresponding to a connecting rodjournal of the crankshaft.
 15. A power train apparatus comprising: anengine including a crankshaft and an engine block; a rotor portionincluding a disk of which a magnet is connected to a side thereofvertical to the crankshaft and the rotor portion connected to thecrankshaft; a stator portion disposed between the rotor portion and themotor housing and including a coil corresponding to the magnet anddisposed vertical to the crankshaft; a transmission; and a clutchselectively transmitting rotation of the rotor portion to thetransmission, wherein a balance portion is formed at the rotor portionfor compensating for imbalance rotational energy transmitted from thecrankshaft.